US7201327B1 - Memory card and its manufacturing method - Google Patents

Abstract

A memory card comprising a die paddle having opposed, generally planar first and second die paddle surfaces and multiple peripheral edge segments. Disposed along and in spaced relation to one of the peripheral edge segments of the die paddle is a plurality of contacts, each of which has opposed, generally planar first and second contact surfaces. An inner body partially encapsulates the die paddle and the contacts, the first contact surface of each of the contacts and the first die paddle surface of the die paddle being exposed in and substantially flush with a generally planar first inner body surface of the inner body. The inner body further defines a generally planar second inner body surface which is disposed in opposed relation to the first inner body surface, the second contact surface of each of the contacts being exposed in the second inner body surface. At least one electronic circuit element is attached to the first die paddle surface and electrically connected to at least one of the contacts. An outer body partially encapsulates the inner body such that the first die paddle surface, the first contact surface of each of the contacts, the first inner body surface and the electronic circuit element are covered by the outer body, with the second inner body surface and hence the second contact surface of each of the contacts not being covered by the outer body and thus exposed.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

Not Applicable

STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT

Not Applicable

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates generally to memory cards, and more particularly to a memory card (e.g., a multi-media card (MMC)) wherein a two-step mold procedure is used to form an outer memory card body which encapsulates an inner memory card body and leadframe structure so that remaining portions of the tie bars used to connect the external signal contacts of the leadframe to the outer frame thereof can be effectively covered by the outer memory card body. The outer body of the memory card of the present invention may also be configured such that the host socket connector pins of a host socket are not damaged by the repeated advancement of the memory card into the host socket.

As is well known in the electronics industry, memory cards are being used in increasing numbers to provide memory storage and other electronic functions for devices such as digital cameras, MP3 players, cellular phones, and personal digital assistants. In this regard, memory cards are provided in various formats, including multi-media cards and secure digital cards.

Typically, memory cards comprise multiple integrated circuit devices or semiconductor dies. The dies are interconnected using a circuit board substrate which adds to the weight, thickness, stiffness and complexity of the card. Memory cards also include electrical contacts for providing an external interface to an insertion point or socket. These electrical contacts are typically exposed on the backside of the circuit board substrate, with the electrical connection to the dies being provided by vias which extend through the circuit board substrate.

In an effort to simplify the process steps needed to fabricate the memory card, there has been developed by Applicant a memory card wherein a leadframe assembly is used an alternative to the circuit board substrate, as described in Applicant's co-pending U.S. application Ser. No. 09/956,190 entitled LEAD-FRAME METHOD AND ASSEMBLY FOR INTERCONNECTING CIRCUITS WITHIN A CIRCUIT MODULE filed Sep. 19, 2001, the disclosure of which is incorporated herein by reference. As is described in Ser. No. 09/956,190, the leadframe and semiconductor die of the memory card are covered with an encapsulant which hardens into a cover or body of the memory card. The body is sized and configured to meet or achieve a “form factor” for the memory card. In the completed memory card, the contacts of the leadframe are exposed within a common surface of the body, with the die pad of the leadframe and the semiconductor die mounted thereto being disposed within or covered by the body.

Memory cards, such as multi-media cards, are used by advancing the same into a host socket which includes a plurality of connector pins. Many host sockets include nine connector pins to accommodate the seven contacts included in many memory card formats such as multi-media cards, and the nine contacts included in the secure digital card memory card format. One of the drawbacks associated with leadframe based memory cards is that portions of the tie bars which are used to connect the contacts to the outer frame of the leadframe are typically exposed in the leading edge of the memory card which is initially advanced into the host socket. More particularly, exposed within this leading edge are the severed ends of the tie bars created as a result of the cutting or singulation process typically used to separate the outer frame of the leadframe from the remainder thereof subsequent to the formation of the body of the memory card. These exposed portions of the tie bars give rise to a potential short against the metal features of the host socket, and are thus highly undesirable. As a result, despite the reduced costs associated with leadframe based memory cards, certain manufacturers are reluctant to use the same due to the potential of generating electrical shorts as described above, and further in view of the appearance of the memory card attributable to the exposure of the severed ends of the tie bars in the leading edge thereof.

Another drawback associated with currently known leadframe based memory cards is their susceptibility to extreme warpage. In this regard, the memory card has a relatively large area, with the thermal expansion coefficients of the memory card body, the leadframe, and the semiconductor die or other internal circuit elements differing from each other. As the capacity of the memory increases, the memory card frequently emits a large amount of heat or receives heat from the device in which it is used. This heat may cause warpage of the memory card, which deteriorates the reliability thereof and may result in the cracking of the internal leadframe or electronic circuit elements.

Yet another deficiency of currently known leadframe based memory cards is that the leading edge of the body thereof is typically fabricated to define a corner which is angled at approximately ninety degrees. This sharp corner, provided on a body typically fabricated from a material significantly harder than general plastic products, often results in some measure of damage to the device into which the memory card is inserted. Such damage is typically evident over time after repeated cycles of the insertion of the memory card into the host socket of the device, the damage often occurring as a result of the contact or rubbing of the sharp leading edge of the memory card against the device.

The present invention addresses and overcomes the above-described deficiencies of currently known leadframe based memory cards by providing a memory card wherein a two-step mold procedure is used to form an outer memory card body which partially encapsulates an inner memory card body itself partially encapsulating the memory card leadframe structure. As a result, the remaining portions of the tie bars used to secure the contacts to the outer frame of the leadframe are completely covered by the outer memory card body. The outer memory card body may further be formed to define a rounded or chamfered leading edge adapted to prevent damage to any device including a host socket into which the memory card is advanced. Also alleviated by the configuration of the memory card of the present invention are many of the warpage problems discussed above. These and other attributes of the present invention will be described in more detail below.

BRIEF SUMMARY OF THE INVENTION

In accordance with the present invention, there is provided multiple embodiments of a memory card. A common feature of each embodiment of the memory card of the present invention is the inclusion of separately molded inner and outer bodies. The inner body is used to at least partially encapsulate the contacts of the memory card and, in certain embodiments, a die paddle to which an electronic circuit element is mounted. An outer body is used to at least partially encapsulate the inner body in a manner covering tie bar residuals integrally connected to and extending from the contacts such that the leading edge of the fully formed memory card is devoid of any exposed metal features. In those embodiments wherein no die paddle is include in the memory card, the electronic circuit element is mounted either directly to the inner body or to an interposer attached to the inner body. The inner body may optionally be formed with surface features which enhance the adhesion to the outer body.

The present invention is best understood by reference to the following detailed description when read in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

These, as well as other features of the present invention, will become more apparent upon reference to the drawings wherein:

FIG. 1A is a bottom perspective view of a memory card constructed in accordance with a first embodiment of the present invention;

FIG. 1B is a cross-sectional view of the memory card shown inFIG. 1A;

FIG. 1C is a top plan view of the leadframe of the memory card of the first embodiment in its final, singulated state, the profile of the outer body of the memory card being shown in phantom;

FIG. 2 is a cross-sectional view of a memory card constructed in accordance with a second embodiment of the present invention;

FIG. 3 is a cross-sectional view of a memory card constructed in accordance with a third embodiment of the present invention;

FIG. 4 is a cross-sectional view of a memory card constructed in accordance with a fourth embodiment of the present invention;

FIG. 5 is a cross-sectional view of a memory card constructed in accordance with a fifth embodiment of the present invention;

FIG. 6 is a cross-sectional view of a memory card constructed in accordance with a sixth embodiment of the present invention;

FIG. 7 is a cross-sectional view of a memory card constructed in accordance with a seventh embodiment of the present invention;

FIG. 8 is a cross-sectional view of a memory card constructed in accordance with an eighth embodiment of the present invention;

FIG. 9 is a cross-sectional view of a memory card constructed in accordance with a ninth embodiment of the present invention;

FIG. 10 is a cross-sectional view of a memory card constructed in accordance with a tenth embodiment of the present invention;

FIG. 11 is a cross-sectional view of a memory card constructed in accordance with a eleventh embodiment of the present invention; and

FIGS. 12A–12F illustrate an exemplary sequence of steps which may be used to facilitate the fabrication of the memory card of the first embodiment shown inFIGS. 1A–1C.

Common reference numerals are used throughout the drawings and detailed description to indicate like elements.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the drawings wherein the showings are for purposes of illustrating preferred embodiments of the present invention only, and not for purposes of limiting the same,FIGS. 1A–1C depict amemory card100 constructed in accordance with a first embodiment of the present invention. Thememory card100 includes a leadframe LF which is shown in its final, singulated state inFIG. 1C and in its original, unsingulated state inFIG. 12A. The leadframe LF of thememory card100 includes adie paddle110 which defines a generally planar first (upper) surface110aand an opposed, generally planar second (lower)surface110b. Thedie paddle110 is preferably formed to have a quadrangular (e.g., square, rectangular) configuration, though other shapes for thedie paddle110 are contemplated to be within the spirit and scope of the present invention.

In addition to thedie paddle110, the leadframe LF of thememory card100 comprises a plurality ofcontacts120 which extend along and in spaced relation to one of the sides or peripheral edge segments of thedie paddle110. Each of thecontacts120 defines a generally planar first (upper) surface120aand an opposed, generally planar second (lower)surface120b. Thedie paddle110 andcontacts120 are arranged such that thefirst surfaces110a,120athereof extend in generally co-planar relation to each other. Integrally connected to and extending from at least some of thecontacts120 toward the die paddle10 is anelongate trace121. Eachtrace121 itself defines a generally planar first (upper) surface121aand an opposed, generally planar second (lower)surface121b. Also integrally connected to eachcontact120 and extending therefrom in a direction opposite to that of thecorresponding trace121 is a tie bar residual122. Each tie bar residual122 itself defines a generally planar first (upper) surface122aand an opposed, generally planar second (lower)surface122b. As best seen inFIG. 2, in the leadframe, thedie paddle110,contacts120, traces121 and tiebar residuals122 are arranged such that thefirst surfaces110a,120a,121a,122athereof extend in generally co-planar relation to each other. However, each of thecontacts120 is formed such that the thickness thereof (i.e., the distance separating the first andsecond surfaces120a,120bfrom each other) exceeds the thicknesses of thedie paddle110, traces121 and tiebar residuals122 which are preferably equal to each other. Thus, while thesecond surfaces110b,121b,122bof thedie paddle110, traces121 and tiebar residuals122 extend in generally co-planar relation to each other, thesecond surfaces120bof thecontacts120 are outwardly offset relative thereto. Thesecond surfaces120bof thecontacts120 extend in generally co-planar relation to each other.

As indicated above, the leadframe LF of thememory card100 is shown inFIG. 1C in its final, singulated state. In its original, unsingulated state as shown inFIG. 12A, tie bars (identified with thereference numeral122 inFIG. 12A) are integrally connected to and extend from each of thecontacts120 to an outer frame F of the leadframe LF. Similarly, thedie paddle110 is integrally connected to and supported within the interior of the outer frame F of the leadframe LF bytie bars122′ which are attached to and extend between thedie paddle110 and the outer frame F. After the formation of aninner body130 of thememory card100 as will be described in more detail below, the leadframe LF is subjected to a number of singulation processes wherein portions of the leadframe LF, and most notably the outer frame F, are removed from the remainder thereof. The completion of the singulation processes (which will be described below) effectively severs the tie bars122 extending to thecontacts120 and the tie bars122′ extending from thedie paddle110 from the outer frame F. As a result of the completion of the singulation processes, only the aforementionedtie bar residuals122 remain upon each of thecontacts120, each of thetie bar residuals122 further defining a lateral surface orouter end122cformed as a result of the severing thereof. Similarly, each of the tie bars122′ defines a lateral surface orouter end122a′ which is formed as a result of a severing thereof from the outer frame F of the leadframe LF.

Prior to its singulation, the leadframe LF of thememory card110 is partially encapsulated by aninner body130 which is formed as a result of the hardening of an encapsulant material applied to the leadframe LF. As seen inFIG. 1B, the encapsulant material is applied to the leadframe LF such that the resultantinner body130 covers thedie paddle110,contacts120, traces121 and tiebar residuals122 in a manner wherein thefirst surfaces110a,120a,121a,122aare exposed in and substantially flush with a generally planar first (upper) surface130aof theinner body130. Thefirst surfaces110a,120a,121a,122a,130athus extend in substantially co-planar relation to each other. In addition to defining thefirst surface130a, theinner body130 defines a generally planar second (lower)surface130bwhich is disposed in opposed relation to thefirst surface130a. Thesecond surfaces130bof thecontacts120 are not covered by theinner body130, and are exposed in thesecond surface130bthereof. Theinner body130 is further formed to define a firstlateral side surface130cand a secondlateral side surface130dwhich is disposed in opposed relation to the firstlateral side surface130c. The severed outer ends122cof thetie bar residuals122 are exposed in and substantially flush with the firstlateral side surface130cof theinner body130. The severed outer ends122a′ of the tie bars122′ are themselves exposed in and substantially flush with respective ones of an opposed pair of first and second longitudinal side surfaces of theinner body130 which extend between the first and second lateral side surfaces130c,130dthereof. As will be recognized, the exposure of the outer ends122cof thetie bar residuals122 in the firstlateral side surface130cand the exposure of the outer ends122a′ of the tie bars122′ in the first and second longitudinal side surfaces of theinner body130 occurs as a result of the singulation of the leadframe LF (i.e., the removal of the outer frame thereof) subsequent to the formation of theinner body130.

The encapsulant used to form theinner body130 may include, for example an epoxy, a plastic molding compound, or equivalents thereto. The thickness of the inner body130 (i.e., the distance separating the first andsecond surfaces130a,130bthereof) is preferably substantially equal to the thickness of each of the contacts120 (i.e., the distance separating the first andsecond surfaces120a,120bthereof). In the fully formedinner body130, thesecond surfaces110b,121b,122bof thedie pad110, traces121 and tiebar residuals122 are covered by theinner body130. It is contemplated the exposedsecond surface120bof eachcontact120 will have aplating layer120cof predetermined thickness applied thereto. Eachplating layer120cis used to assist in the electrical connection of thememory card100 to an external device, and may be fabricated from any suitable conductive material, such as Au, Ag, Sn/Pb, or their equivalents. Advantageously, the difference in the thicknesses between eachcontact120 and thetraces121 and tiebar residuals122 connected thereto, and resultant underflow of encapsulant material over thesecond surfaces121b,122b, effectively increases the bonding forces or force of adhesion between theinner body130 and thecontacts120, traces121 and tiebar residuals122.

Thememory card100 of the first embodiment further comprises at least oneelectronic circuit element140 which is attached to thefirst surface110aof thedie paddle110 through the use of alayer140aof suitable adhesive. Such adhesive may include, for example, an adhesive film/tape, an anisotropic conductive film/paste, epoxy, or an equivalent thereto. Theelectronic circuit element140 itself may comprise asemiconductor package141, asemiconductor die142, and/or apassive element143, but is not limited thereto. Further, theelectronic circuit element140 may take a form in which two or more elements are stacked. Although the electronic circuit element40 is shown inFIG. 1B as including three components (thesemiconductor package141, semiconductor die142 and passive element143), those of ordinary skill in the art will recognize that this particular combination is illustrative only, in that the nature and number of the components included in theelectronic circuit element140 may be varied, and provided in a multiplicity of different combinations. In the configuration shown inFIG. 1B, aconductive wire150 is used to electrically connect theelectronic circuit element140 to one or more of thecontacts120 via one or more of thetraces121. In this regard, theconductive wire150 shown inFIG. 1B extends and is electrically connected to thetrace121, which is in turn integrally connected to acorresponding contact120.Conductive wires150 may also be used to connect theelectronic circuit element140 to thedie paddle110, and/or the various components of theelectronic circuit element140 to each other. The conductive wire(s)150 may be fabricated from, for example Au, Al, Cu, or equivalents thereto. It is contemplated that alternatives to theconductive wires150 may be used to facilitate the electrical connection of theelectronic circuit element140 to one ormore contacts120. More particularly, though not shown, conductive bumps, conductive adhesive, or equivalents thereto may be used to facilitate such electrical connection.

The leadframe LF of thememory card100 is preferably fabricated from a conductive metal material (e.g., copper) through either a chemical etching or mechanical stamping process. Those of ordinary skill in the art will recognize that the leadframe LF may be formed to include any number ofcontacts120 depending on the desired application for thememory card100. Thus, the number ofcontacts120 shown inFIGS. 1A and 1C is exemplary only. Additionally, rather than being attached to thefirst surface110aof thedie paddle110, it is contemplated that the leadframe LF may alternatively be configured such that thedie paddle110 is completely eliminated therefrom, the size of thetraces121 being increased to a point wherein theelectronic circuit element140 may be attached directly to portions thereof. Further, the pattern of thetraces121 may also be varied depending on the number ofcontacts120 and the number of components included in theelectronic circuit element140. Thus, the configuration of the leadframe LF of thememory card100 is variable, in that the number and arrangement of components in theelectronic circuit element140, the number ofcontacts120, and the number and arrangement ofconductive traces121 may be varied as needed to satisfy the requirements of a particular application.

After theinner body130 has been applied to the leadframe LF in the above-described manner, and theelectronic circuit element140 has been attached to thedie paddle110 and electrically connected the leadframe through the use of theconductive wires150, anouter body160 is formed to partially cover theinner body130, leadframe LF, andelectronic circuit element140. As best seen inFIGS. 1A and 1B, theouter body160 defines a generally planar first (upper) surface160a. Formed in thefirst surface160ais a detent orrecess160fwhich is sized and configured to accommodate alabel170 which is fixed to theouter body160 subsequent to the formation thereof. The receipt of thelabel170 into therecess160fprevents thelabel170 from shifting or otherwise becoming displaced relative to theouter body160.

In the completedmemory card100, theouter body160 further defines a firstlateral side surface160cand a secondlateral side surface160dwhich is disposed in opposed relation to the firstlateral side surface160c. The first and second lateral side surfaces160c,160deach extend at approximately a right angle relative to thefirst surface160a. Theouter body160 is preferably formed such that the secondlateral side surface160dthereof is substantially continuous with the secondlateral side surface130dof theinner body130 as seen inFIG. 1B. Additionally, as seen inFIG. 1A, it is contemplated that theouter body160 will include an opposed pair of first and second longitudinal side surfaces which extend between the first and second lateral side surfaces160c,160dthereof, and are substantially continuous with respective ones of the first and second longitudinal side surfaces of theinner body130. The firstlateral side surface160cof theouter body160 transitions to a rounded corner orsurface160e. Therounded surface160eextends to and is substantially flush with thesecond surface130bof theinner body130. Therounded surface160edefines the leading edge of thememory card100, and is specifically configured to prevent the device into whichmemory card100 is inserted from being scratched or otherwise damaged by thememory card100 as a result of such insertion.

Theouter body160, when fully formed, completely covers theelectronic circuit element140 and theconductive wires150. Also covered by theouter body160 are the exposed portions of thefirst surfaces110a,120a,121a,122a,130aof thedie paddle110,contacts120, traces121,tie bar residuals122, andinner body130. Importantly, theouter body160 also covers the firstlateral side surface130cof theinner body130 and the outer ends122cof thetie bar residuals122 exposed therein. Thus, the outer ends122cof thetie bar residuals122 are not exposed in the completedmemory card100, with no metal at all being exposed in firstlateral side surface160cor roundedsurface160eof theouter body160. Though the outer ends122a′ of the tie bars122′ are exposed in respective ones of the first and second longitudinal side surfaces of theinner body130 and are not covered by the outer body160 (as shown inFIG. 1A), such exposure is not problematic since such outer ends122a′ are not located near thecontacts120 and are not advanced into the host socket, thus creating little risk of generating electrical shorts between the tie bars122′ and an external device into which thememory card100 is inserted.

In thememory card100, it is contemplated that the encapsulant material used to form theouter body160 may have a thermal expansion co-efficient similar to that of the encapsulant material used to form theinner body130. In this regard, the encapsulant material used to form the inner andouter bodies130,160 may be identical. Thus, it is possible to effectively prevent warpage caused by the difference among the thermal expansion coefficients of thedie paddle110, thecontacts120, and theelectronic circuit element140. The encapsulant material used to form theinner body130 and/or theouter body160 may include, for example, an epoxy, a plastic molding compound, or equivalents thereto, the present invention not being limited to any specific materials for the inner andouter bodies130,160.

Referring now toFIGS. 12A–12F, there is shown an exemplary sequence of steps which may be used to facilitate the fabrication of thememory card100 of the first embodiment of the present invention. In the initial step of the sequence, the above-described unsingulated leadframe (identified inFIG. 12A as with the reference letters LF) is provided, and partially encapsulated with the inner body130 (FIG. 12A). As also indicated above, in its unsingulated state, the leadframe LF includes an outer frame (identified inFIGS. 12A–12E with the reference letter F). InFIG. 12A, the tie bars122 attached to and extending between the outer frame F and respective ones of thecontacts120 are shown, though the tie bars122′ attached to and extending between thedie paddle110 and the outer frame F are not shown.

Subsequent to the formation of theinner body130, an initial singulation process is completed to facilitate the severing of the tie bars122 from the outer frame F. More particularly, a portion of the leadframe LF is subjected to a punching, laser, or other singulation process which effectively causes a hole H to be formed through a portion of theinner body130, the formation of such hole H also facilitating the removal of substantial portions of the tie bars122 from the leadframe LF (FIG. 12B). In this regard, only one small segment of eachtie bar122 remains subsequent to the formation of the hole H, such remaining segment being identified as the tie bar residual122 inFIGS. 12B–12F (as well asFIGS. 1B and 1C). Despite the removal of substantial portions of the tie bars122 as a result of the formation of the hole H, thecontacts120 are maintained in prescribed spatial relationships relative to each other by the partial encapsulation thereof within theinner body130. It should be noted that theinner body130, when initially formed, fills the interior of the outer frame F of the leadframe LF.

Subsequent to the formation of the hole H and partial removal of the tie bars122 (FIG. 12B), theelectronic circuit element140 is adhered to thefirst surface110aof thedie paddle110 of the leadframe LF through the use of thelayers140 of adhesive (FIG. 12C). Thereafter, a wire bonding process is completed to facilitate the electrical connection of theelectronic circuit element140 to the leadframe LF through the use of the conductive wire(s)150 in the above-described manner (FIG. 12D).

In the next step of the fabrication sequence for thememory card100, theouter body160 is formed to have the above-described structural attributes (FIG. 12E). As indicated above, theouter body160 covers thefirst surfaces110a,120a,121a,122a,130aof thedie paddle110, thecontacts120, thetraces121, thetie bar residuals122 and theinner body130. Also covered by theouter body160 are theelectronic circuit element140 and conductive wire(s)150. The encapsulant material which hardens to form theouter body160 also flows into the hole H, thus resulting in theouter body160 covering the outer ends122cof thetie bar residuals122 in addition to the firstlateral side surface130cof theinner body130. Subsequent to the formation of theouter body160, the leadframe LF is subjected to a follow-up singulation process which facilitates the severing of the tie bars122′ and removal of the outer frame F (FIG. 12F). Such severing of the tie bars122′ results in the exposure of the outer ends122a′ in respective ones of the first and second longitudinal side surfaces of theinner body130 in the above-described manner. The removal of the outer frame F completes the fabrication of thememory card100. Those of ordinary skill in the art will recognize that the construction of thememory card100 is not necessarily limited to the precise order or sequence of steps described above.

Referring now toFIG. 2, there is shown amemory card200 constructed in accordance with a second embodiment of the present invention. Thememory card200 of the second embodiment bears substantial similarity in construction to thememory card100 of the first embodiment, with the200 series reference numerals inFIG. 2 being used to identify the same structures identified by the corresponding100 series reference numerals included inFIGS. 1A–1C. In this regard, only the distinctions between thememory cards200,100 will be discussed below.

The primary distinction between thememory cards100,200 lies in the absence of any die paddle in the leadframe of thememory card200. In this regard, in contrast to the leadframe LF of thememory card100 which includes thedie paddle110, such die paddle is not included in the leadframe of thememory card200. As a result, theelectronic circuit element240 of thememory card200 is attached directly to thefirst surface230aof theinner body230. In thememory card200 as shown inFIG. 2, theelectronic circuit element240 attached directly to theinner body230 via thelayers240aof a suitable adhesive differs from theelectronic circuit element140 due to the absence in theelectronic circuit element240 of thepassive element143 described in relation to theelectronic circuit element140. In theelectronic circuit element240, aconductive wire250 is used to electrically connect thesemiconductor package241 and the semiconductor die242 to each other, with aconductive wire250 also being used to facilitate the electrical connection of thesemiconductor package241 of theelectronic circuit element240 to at least one of thecontacts220 via at least one of thetraces221.

Thememory card200 further differs from thememory card100 in that theouter body260 of thememory card200 is not formed to include therounded surface160edescribed above in relation to theouter body160. In this respect, theouter body260 of thememory card200 includes a generally planar second (lower)surface260bwhich extends in generally co-planar relation to thesecond surface230bof theinner body230. The firstlateral side surface260cof theouter body260 extends generally perpendicularly between the first andsecond surfaces260a,260bthereof. The fabrication methodology for thememory card200 closely mirrors that of thememory card100, with the primary distinction lying in the attachment of theelectronic circuit element240 to thefirst surface230aof theinner body230 as opposed to a die paddle.

Referring now toFIG. 3, there is shown amemory card300 constructed in accordance with a third embodiment of the present invention. Thememory card300 of the third embodiment bears substantial similarity in construction to thememory card200 of the second embodiment, with the300 series reference numerals inFIG. 3 being used to identify the same structures identified by the corresponding200 series reference numerals included inFIG. 2 and the corresponding100 series reference numerals included inFIGS. 1A–1C. Only the distinctions between thememory cards300,200 will be discussed below.

Thememory card300 of the third embodiment differs from thememory card200 in that theelectronic circuit element340 of thememory card300 is attached to one side or face of a generallyplanar interposer310 through the use oflayers340aof a suitable adhesive. The surface of theinterposer310 opposite that having theelectronic circuit element340 attached thereto is itself attached to the generally planarfirst surface330aof theinner body330 of thememory card300. Theinterposer310, which preferably includes various circuit patterns, may be a printed circuit board, a circuit tape, a circuit film, or equivalents thereto. Though not shown inFIG. 3, it is contemplated that theinterposer310 will have a plurality of circuit patterns formed on the surfaces and/or within the interior thereof. In thememory card300, aconductive wire350 may be used to electrically connect theelectronic circuit element340 to theinterposer310. The manufacturing methodology for thememory card300 closely mirrors that of thememory card200, except that theelectronic circuit element340 is attached to theinterposer310 which is itself attached to theinner body330, as opposed to theelectronic circuit element340 being directly attached to theinner body330. The inclusion of theinterposer310 in thememory card300 allows theelectronic circuit element340 integrated into thememory card300 to be of increased capacity.

Referring now toFIG. 4, there is shown amemory card400 constructed in accordance with a fourth embodiment of the present invention. Thememory card400 of the fourth embodiment bears substantial similarity to thememory card200 of the second embodiment, with the400 series reference numerals inFIG. 4 being used to identify the same structures identified by the corresponding200 series reference numerals included inFIG. 2.

In thememory card400, theouter body460 is formed to cover a substantial portion of thesecond surface430bof theinner body430. More particularly, that portion of theouter body460 covering thesecond surface430bof theinner body430 extends to approximately the second surfaces420bof thecontacts420. As is further seen inFIG. 4, in thememory card400, theouter body460 is also formed to defineintegral rail portions460′ which extend between adjacent pairs of thecontacts420 toward the firstlateral side surface460cof theouter body460. The lower edge of eachrail portion460′ is substantially flush or continuous with thesecond surface460bof theouter body460. Therail portions460′ each extend over a portion of thesecond surface430bof theinner body430 which is labeled with thereference numeral430b′ inFIG. 4. Thesecond surface portion430b′ of theinner body430 is located between the second surfaces420bof thecontacts420 and the firstlateral side surface460cof theouter body460. As will be recognized, portions or sections of thesecond surface portion430b′ which are not covered by therail portions460′ remain exposed in the fully formedmemory card400.

As is further seen inFIG. 4, portions of thesecond surface460bof theouter body460 labeled with thereference numeral460b′ are perpendicularly or vertically recessed relative to the remainder of thesecond surface460. Thesesecond surface portions460b′ of theouter body460 are located between the firstlateral side surface460cand thesecond surface portion430b′ of theinner body430. In theouter body460 of thememory card400, therounded surface460eis not continuous, but rather is segmented due to the formation of therail portions460′ in theouter body460. The increased thickness of theouter body460 in thememory card400 facilitates an improvement in the mechanical strength thereof, therefore reducing its susceptibility to being easily broken by the application of external forces thereto.

Referring now toFIG. 5, there is shown amemory card500 constructed in accordance with a fifth embodiment of the present invention. Thememory card500 of the fifth embodiment bears similarity to thememory card200 of the second embodiment, with the500 series reference numerals inFIG. 5 being used to identify the same structures identified by the corresponding200 series reference numerals included inFIG. 2. Only the distinctions between thememory cards500,200 will be discussed below.

In thememory card500, theinner body530 is formed such that a substantial portion of thesecond surface530bof theinner body530 does not extend in co-planar relation to thesecond surfaces520bof thecontacts520 or to the outermost surfaces of the plating layers520capplied to thesecond surfaces520b, but rather protrudes vertically or perpendicularly outwardly relative thereto. Thus, as is seen inFIG. 5, only a portion of thesecond surface530blabeled with thereference numeral530b′ extends in generally co-planar relation to either thesecond surfaces520bof thecontacts520 or the outermost surfaces of the plating layers520capplied to thesecond surfaces520b. Thesecond surface portion530b′ of theinner body530 is disposed between thesecond surfaces520bof thecontacts520 and thesecond surface560bof theouter body560. The increased thickness of theinner body530 of thememory card500 makes it less susceptible to being broken by external forces due to its increased mechanical strength.

Referring now toFIG. 6, there is shown amemory card600 constructed in accordance with a sixth embodiment of the present invention. Thememory card600 of the sixth embodiment bears similarity in construction to thememory card100 of the first embodiment, with the600 series reference numerals inFIG. 6 being used to identify the same structures identified by the corresponding100 series reference numerals included inFIGS. 1A–1C. Only the distinctions between thememory cards600,100 will be discussed below.

In thememory card600, the thickness of theinner body630 is increased in comparison to that of theinner body130, such that theinner body630 of thememory card600 fully covers and encapsulates both thedie paddle610 and theelectronic circuit element640 mounted to thefirst surface610aof thedie paddle610. In addition, theinner body630 is formed to cover thefirst surfaces620aof thecontacts620 and thefirst surfaces621aof thetraces621. Thus, of the leadframe included in thememory card600, only thefirst surfaces622aandouter ends622cof thetie bar residuals622 and thesecond surfaces620bof the contacts620 (prior to having the plating layers620capplied thereto) are exposed in theinner body630.

As is further seen inFIG. 6, theinner body630 is formed such that a portion of the firstlateral side surface630clabeled with thereference630c′ is recessed inwardly relative to the remainder of the firstlateral side surface630c. Similarly, a portion of the secondlateral side surface630dlabeled with thereference numeral630d′ is recessed inwardly relative to the remainder of the secondlateral side surface630d. The first lateralside surface portion630c′ and the second lateralside surface portion630d′ are each covered by theouter body660 of thememory card600. Like thememory card200 of the second embodiment, thememory card600 is further distinguishable from thememory card100 in that theouter body660 does not include therounded surface160edescribed above in relation to theouter body160, nor does theelectronic circuit element640 include thepassive element143 of theelectronic circuit element140.

Referring now toFIG. 7, there is shown amemory card700 constructed in accordance with a seventh embodiment of the present invention. Thememory card700 of the seventh embodiment bears substantial similarity in construction to thememory card600 of the sixth embodiment, with the700 series reference numerals inFIG. 7 being used to identify the same structures identified by the corresponding600 series reference numerals included inFIG. 6. Only the distinctions between thememory cards700,600 will be discussed below.

Thememory card700 differs from thememory card600 in that theinner body730 of thememory card700 is formed to be slightly smaller than that of theinner body630 of thememory card600. In this regard, whereas theinner body630 is sized to cover both thefirst surfaces620aof thecontacts620 andfirst surfaces621aof thetraces621, thefirst surfaces720aof thecontacts720 in thememory card700 are not covered by theinner body730 thereof. Thus, of the various elements included in the leadframe in thememory card100, thedie paddle710 and traces721 are fully covered by theinner body730, with thefirst surfaces720aof thecontacts720,first surfaces722aandouter ends722cof thetie bar residuals722, and thesecond surfaces720bof the contacts720 (prior to the application of the plating layers720cthereto) being exposed in theinner body730.

Referring now toFIG. 8, there is shown amemory card800 constructed in accordance with an eighth embodiment of the present invention. Thememory card800 of the eighth embodiment bears similarity in construction to thememory card700 of the seventh embodiment, with the800 series reference numerals inFIG. 8 being used to identify the same structures identified by the corresponding700 series reference numerals isFIG. 7. Only the distinctions between thememory cards800,700 will be discussed below.

In thememory card800, thedie paddle810 of the leadframe is offset such that thefirst surface810aof thedie paddle810 and thefirst surfaces820aof thecontacts820 extend along respective ones of a spaced, generally parallel pair of planes. Such offset of thedie paddle810 is facilitated through the formation of an angled orsloped portion823 within each of thetraces821 of the leadframe integrated into thememory card800. As is seen is seen inFIG. 8, both thedie paddle810 and theelectronic circuit element840 mounted to thefirst surface810athereof through the use of theadhesive layer840aare completely covered by theinner body830, as is the entirety of the traces821 (including the slopedportions823 thereof), the first surfaces of820aof thecontacts820, and the first andsecond surfaces822a,822bof thetie bar residuals822. Also covered by theinner body830 is/are the conductive wire(s)850 used to electrically connect theelectronic circuit element840 to the trace(s)821. The outer ends822cof thetie bar residuals822 are exposed in and substantially flush with the firstlateral side surface830cof theinner body830, with thesecond surfaces820bof the contacts820 (prior to the application of the plating layers820cthereto) being exposed in thesecond surface830bof theinner body830. Once the plating layers820care applied to thesecond surfaces820b, such plating layers820care exposed in thesecond surface830bof theinner body830.

In thememory card800, theouter body860 is formed to completely cover thefirst surface830a, firstlateral side surface830c, and secondlateral side surface830dof theinner body830. Thesecond surface830bof theinner body830 is exposed in and substantially flush with thesecond surface860bof theouter body860. Due to the configuration of theouter body860, the outer ends822cof thetie bar residuals822 exposed in the firstlateral side surface830cof theinner body830 are completely covered by theouter body860.

Referring now toFIG. 9, there is shown amemory card900 constructed in accordance with a ninth embodiment of the present invention. Thememory card900 of the ninth embodiment bears similarity in construction to thememory card700 of the seventh embodiment, with the900 series reference numerals inFIG. 9 being used to identify the same structures identified by the corresponding700 series reference numerals included inFIG. 7. In this regard, only the distinctions between thememory cards900,700 will be discussed below.

In thememory card900, theinner body930 is substantially smaller than theinner body730 of thememory card700. In this regard, theinner body930 of thememory card900 is formed such that only the first andsecond surfaces922a,922bof thetie bar residuals922, thefirst surfaces920aof thecontacts920, and portions of the first andsecond surfaces921a,921bof thetraces921 are covered by theinner body930. Substantial portions of thetraces921 protrude from the secondlateral side surface930bof theinner body930, with thesecond surfaces920bof the contacts920 (prior to the application of the plating layers920cthereto) being exposed in thesecond surface930bof theinner body930. The outer ends922cof thetie bar residuals922 are exposed in and substantially flush with the firstlateral side surface930cof theinner body930. The protrusion of substantial portions of thetraces921 from theinner body930 allows for connection of the conductive wire(s)950 thereto. The conductive wire(s)950 is/are used to electrically connect theelectronic circuit element940 to the trace(s)921 and hence the contact(s)920.

In thememory card900, theouter body960 is sized and configured to completely cover thedie paddle910, theelectronic circuit element940 attached to thefirst surface910aof thedie paddle910 through the use of theadhesive layers940a, the conductive wire(s)950, and those portions of thetraces921 protruding from the secondlateral side surface930dof theinner body930. Theouter body960 further covers thefirst surface920aand first and second lateral side surfaces930c,930dof the inner body (and hence the outer ends922cof thetie bar residuals922 exposed in the firstlateral side surface930c). Thus, only thesecond surface930bof theinner body930 is exposed in and substantially flush with thesecond surface960bof theouter body960.

Referring now toFIG. 10, there is shown amemory card1000 constructed in accordance with a tenth embodiment of the present invention. Thememory card1000 of the tenth embodiment bears similarity in construction to thememory card200 of the second embodiment, with the1000 series reference numerals inFIG. 10 being used to identify the same structures identified with the corresponding200 series reference numerals inFIG. 2. Only the distinctions between thememory cards1000,200 will be discussed below.

Thememory cards1000,200 differ from each other in that theinner body1030 of thememory card1000 is formed to include at least oneprojection1030eprotruding upwardly from thefirst surface1030athereof. Theprojection1030emay be formed at any position on thefirst surface1030a, but preferably at a location which is outboard of theelectronic circuit element1040 attached to thefirst surface1030a. As shown inFIG. 10, a plurality ofprojections1030eare formed on thefirst surface1030aof theinner body1030. The height or thickness of the projection(s)1030eis preferably controlled so that they will not contact any of theconductive wires1050 used to electrically connect theelectronic circuit element1040 to the leadframe integrated into thememory card1000. The inclusion of the projection(s)1030eon theinner body1030 increases the bonding force between theinner body1030 and theouter body1060, thus assisting in preventing inadvertent separation therebetween.

Referring now toFIG. 11, there is shown amemory card1100 constructed in accordance with an eleventh embodiment of the present invention. Thememory card1100 of the eleventh embodiment bears similarity in construction to thememory card1000 of the tenth embodiment, with the1100 series reference numerals inFIG. 11 being used to identify the same structures identified with the corresponding1000 series reference numerals inFIG. 10. Only the distinctions between thememory cards1100,1000 will be discussed below.

Thememory card1100 differs from thememory card1000 in that in thememory card1100, theinner body1130 is sized and configured to completely cover thefirst surfaces1122aof thetie bar residuals1122, thefirst surfaces1120aof thecontacts1120, and thefirst surfaces1121aof thetraces1120. Additionally, the width of at least one of theprojections1130eis increased so as to extend to and into contact with theelectronic circuit element1140. Like theprojections1030eof thememory card1000, theprojections1130eof theinner body1130 of thememory card1100 increase the bonding force to theouter body1160 thereof.

This disclosure provides exemplary embodiments of the present invention. The scope of the present invention is not limited by these exemplary embodiments. Numerous variations, whether explicitly provided for by the specification or implied by the specification, such as variations in structure, dimension, type of material and manufacturing process may be implemented by one of skill in the art in view of this disclosure.

Claims (29)

1. A memory card, comprising:

a die paddle having opposed, generally planar first and second die paddle surfaces and multiple peripheral edge segments;

a plurality of contacts disposed along and in spaced relation to one of the peripheral edge segments of the die paddle, each of the contacts having opposed, generally planar first and second contact surfaces;

an inner body partially encapsulating the die paddle and the contacts, the inner body having opposed, generally planar first and second inner body surfaces, the first die paddle surface and the first contact surface of each of the contacts being exposed in and substantially flush with the first inner body surface, with the second contact surface of each of the contacts being exposed in the second inner body surface;

at least one electronic circuit element attached to the first die paddle surface and electrically connected to at least one of the contacts; and

an outer body partially encapsulating the inner body such that the first contact surface of each of the contacts, the first die paddle surface, the electronic circuit element, and the first inner body surface are covered by the outer body, and the second inner body surface is exposed in the outer body.

2. The memory card ofclaim 1 wherein the electronic circuit element is electrically connected to at least one of the contacts via at least one conductive wire which is covered by the outer body.

3. The memory card ofclaim 1 wherein each of the contacts has a contact thickness between the first and second contact surfaces thereof which exceeds a paddle thickness of the die paddle between the first and second die paddle surfaces thereof.

4. The memory card ofclaim 1 wherein the first die paddle surface and the first contact surface of each of the contacts extend in generally co-planar relation to each other.

5. The memory card ofclaim 1 wherein the second contact surface of each of the contacts includes a plating layer applied thereto which is exposed in the second inner body surface of the inner body.

6. The memory card ofclaim 1 further comprising:

a plurality of conductive traces integrally connected to respective ones of at least some of the contacts and extending toward the die paddle in spaced relation thereto, each of the traces having opposed, generally planar first and second trace surfaces; and

a plurality of tie bar residuals integrally connected to respective ones of the contacts and extending toward the outer body, each of the tie bar residuals having opposed, generally planar first and second tie bar surfaces.

7. The memory card ofclaim 6 wherein:

the die paddle has a die paddle thickness between the first and second die paddle surfaces thereof;

each of the traces has a trace thickness between the first and second trace surfaces thereof which is substantially equal to the die paddle thickness; and

each of the tie bar residuals has a tie bar thickness between the first and second tie bar surfaces thereof which is substantially equal to the die paddle thickness.

8. The memory card ofclaim 6 wherein:

each of the tie bar residuals further includes a generally planar outer end; and

the inner body has a generally planar first lateral side surface, the outer ends of the tie bar residuals being exposed in and substantially flush with the first lateral side surface of the inner body.

9. The memory card ofclaim 8 wherein the first lateral side surface of the inner body and the outer ends of the tie bar residuals exposed therein are covered by the outer body.

10. The memory card ofclaim 1 wherein the outer body has a first lateral side surface and a rounded surface which extends between the first lateral side surface of the outer body and the second inner body surface of the inner body.

11. The memory card ofclaim 1 wherein:

the inner body has opposed, generally planar first and second lateral side surfaces; and

the outer body has opposed, generally planar first and second lateral side surfaces; and

the second lateral side surface of the inner body extends in generally co-planar relation to the second lateral side surface of the outer body.

12. The memory card ofclaim 1 wherein the electronic circuit element is selected from the group consisting of:

a semiconductor package;

a semiconductor die;

a passive element; and

combinations thereof.

13. The memory card ofclaim 1 wherein at least one of the contacts is integrally connected to the die paddle.

14. A memory card, comprising:

a plurality of contacts, each of the contacts having opposed, generally planar first and second contact surfaces;

an inner body partially encapsulating the contacts, the inner body having opposed, generally planar first and second inner body surfaces, the first contact surface of each of the contacts being exposed in and substantially flush with the first inner body surface, with the second contact surface of each of the contacts being exposed in the second inner body surface;

at least one electronic circuit element attached to the first inner body surface and electrically connected to at least one of the contacts; and

an outer body partially encapsulating the inner body such that the first contact surface of each of the contacts, the electronic circuit element, and the first inner body surface are covered by the outer body, and the second inner body surface is exposed in the outer body.

15. The memory card ofclaim 14 wherein the electronic circuit element is electrically connected to at least one of the contacts via at least one conductive wire which is covered by the outer body.

16. The memory card ofclaim 14 wherein the second contact surface of each of the contacts includes a plating layer applied thereto which is exposed in the second inner body surface of the inner body.

17. The memory card ofclaim 14 wherein:

an interposer is attached to the first inner body surface of the inner body; and

the electronic circuit element is attached and electrically connected to the interposer.

18. The memory card ofclaim 14 further comprising:

a plurality of conductive traces integrally connected to respective ones of at least some of the contacts and extending toward the electronic circuit element, each of the traces having opposed, generally planar first and second trace surfaces; and

a plurality of tie bar residuals integrally connected to respective ones of the contacts and extending toward the outer body, each of the tie bar residuals having opposed, generally planar first and second tie bar surfaces.

19. The memory card ofclaim 18 wherein:

each of the tie bar residuals further includes a generally planar outer end; and

the inner body has a generally planar first lateral side surface, the outer ends of the tie bar residuals being exposed in and substantially flush with the first lateral side surface of the inner body.

20. The memory card ofclaim 19 wherein the first lateral side surface of the inner body and the outer ends of the tie bar residuals exposed therein are covered by the outer body.

21. The memory card ofclaim 18 wherein:

each of the contacts has a contact thickness between the first and second contact surfaces thereof;

each of the traces has a trace thickness between the first and second trace surfaces thereof which is less than the contact thickness; and

each of the tie bar residuals has a tie bar thickness between the first and second tie bar surfaces thereof which is less than the contact thickness.

22. The memory card ofclaim 14 wherein:

each of the contacts has a contact thickness between the first and second contact surfaces thereof; and

at least a portion of the inner body has an inner body thickness between the first and second inner body surfaces thereof which exceeds the contact thickness.

23. The memory card ofclaim 14 wherein the outer body is formed to cover at least a portion of the second inner body surface of the inner body.

24. A memory card, comprising:

a die paddle having opposed, generally planar first and second die paddle surfaces and multiple peripheral edge segments;

a plurality of contacts disposed along and in spaced relation to one of the peripheral edge segments of the die paddle, each of the contacts having opposed, generally planar first and second contact surfaces;

at least one electronic circuit element attached to the first die paddle surface and electrically connected to at least one of the contacts;

an inner body encapsulating the die paddle and the electronic circuit element and partially encapsulating the contacts, the inner body having opposed, generally planar first and second inner body surfaces, with the second contact surface of each of the contacts being exposed in the second inner body surface; and

an outer body partially encapsulating the inner body such that the second inner body surface is exposed in the outer body.

25. The memory card ofclaim 24 wherein the first contact surface of each of the contacts is covered by the outer body.

26. The memory card ofclaim 24 wherein the first contact surface of each of the contacts and the first die paddle surface of the die paddle extend along respective ones of a spaced, generally parallel pair of planes.

27. A memory card, comprising:

a die paddle having opposed, generally planar first and second die paddle surfaces and multiple peripheral edge segments;

a plurality of contacts disposed along and in spaced relation to one of the peripheral edge segments of the die paddle, each of the contacts having opposed, generally planar first and second contact surfaces;

at least one electronic circuit element attached to the first die paddle surface and electrically connected to at least one of the contacts;

an inner body partially encapsulating the contacts, the inner body having opposed, generally planar first and second inner body surfaces, the second contact surface of each of the contacts being exposed in the second inner body surface; and

an outer body encapsulating the die paddle and the electronic circuit element and partially encapsulating the inner body such that the first inner body surface is covered by the outer body, and the second inner body surface is exposed in the outer body.

28. A memory card, comprising:

a plurality of contacts, each of the contacts having opposed, generally planar first and second contact surfaces;

an inner body partially encapsulating the contacts, the inner body having opposed first and second inner body surfaces, the second contact surface of each of the contacts being exposed in the second inner body surface, with the first inner body surface further including at least one projection formed thereon;

at least one electronic circuit element attached to the first inner body surface and electrically connected to at least one of the contacts; and

an outer body partially encapsulating the inner body such that the electronic circuit element, the first inner body surface, and the at least one projection are covered by the outer body, and the second inner body surface is exposed in the outer body.

29. The memory card ofclaim 28 wherein the inner body is formed to cover the first contact surface of each of the contacts.

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